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How To Write Effective Subject Lines

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Author

Fil from Bedford
December 18, 2024 • Reading time: 6 minutes

GM! Paperboy here 🗞️

The subject of this email was written by dbrand. It inspired me to write this email. Click the link to read the email that followed. It’s good.

Today’s Golden Nugget: Put The Sale In The Subject Line

You might think you’re being mysterious and clickbait writing a subject line like “Our sale just started”. Maybe you are… but it’s hurting your bottom line.

I’ve tested this extensively across dozens of brands and something like “Valentine’s Sale 💘 30% Off” does much better than copy like “Our Valentine’s Sale Is Here…” or “Save BIG During Our Valentine’s Sale”.

Today’s Issue: How To Write Effective Subject Lines

A great subject line doesn’t just increase open rates. It sparks emotion and sets an expectation of what’s to come.

I’ll share a condensed version of the training I give my team to write effective subject lines.

Length: Keep it short

Subject lines and preview text get cut off when too long. Assume if it’s not visible in the inbox, they’ll never see it.

Keep it to 7 words if using short words (e.g. Fresh, Meet, Collab), 4 or 5 if using long words (Dropping, Holiday, Surprise). Less is more.

Ruggable is great at this.

Simplicity: Keep it simple stupid (for The Office fans)

Stop cramming sales, products, and reviews all into a single subject.

Humans are terrible at multi-tasking. When you share too much, they only remember the last thing.

Pick one key message and have everything support it.

Loop nails this - every email has one goal. They did $130M in revenue last year.

Emotion: make them feel something

I know, how cliche. But of the 300+ emails I read every day, most brands do a poor job at this.

The best subject lines make you curious, excited, or even FOMO-struck.

Figure out what that should be for your brand.

Example emotions:

Resource: 8 Core Emotions taken from Shaan Puri’s course

I took Shaan Puri’s course a while back and this list has always stuck with me. I use it as inspiration.

Emojis: Use them in moderation

When using emojis, try to use 1 emoji total, ideally in the subject line.

Don’t put emojis right at the start of a subject line. This is a deliverability killer.

Overusing 🚨🔔🎁 will annoy people and lead to more unsubs. There are 3,700+ other emojis to choose from.

Validate Ideas: AB test subject lines on each email

Every campaign should have subject line AB tests (unless you’re running content tests).

Test angles, benefits, emotions, etc.

Go back monthly and see what tests worked and ask yourself why. Then plan next month’s tests.

Spam: Beware of trigger words

Avoid using words like:

  • Act Now

  • Bargain/Cheap

  • Cash, Money, Dollar Signs ($$)

  • Urgent/Important

  • Winner/Won

Avoid using these right at the start of the subject line:

  • Guarantee/Promise

  • XX% OFF

  • Free

  • Emojis

Use your best judgment.

Brainstorming: Use AI for better output

This is my #1 hack.

Create an AI master document that contains:

  • Information about your brand

  • Survey results

  • Customer pain points

  • Product benefits

  • Website copy

  • 200 Relevant subject lines & preview texts from other brands you like (use Milled)

Plug the document into a Claude Project and prompt it things like:

  • I’m writing an email about X, give me 100 subject & preview text combinations

  • Help me shorten this subject line 30 ways

  • Give me 30 cultural references or puns that could work with this email concept as a subject line

I made a Notion starter template for you with the instructions from this email here. Copy paste it directly into Claude or ChatGPT.

Test your sends

Send yourself a test. Ideally to both an iPhone and a computer running gmail.

Break the rules

Don’t stick to the same formula year-round.

Reinvent yourself, ideally around big sales.

Write frame-breaking subject lines.

Examples of brands with good subject lines

That’s all for now. Now get to writing!

Meme of the Day:

Thanks for reading,
Paperboy 🗞️

p.s. Did you like the newsletter? Hate it? Reply and tell me why! I read and reply to every message.

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